Reproducing piano



Aug. 16,1927. 1,539,105

s. H. PERRON REPRODUCING PIANO Filed July 12, 1921 9 Sheets-Sheet l TRACKER C SELECTOR, 35

SELECTOR A SELECTOR 33 SELECTOR CONTROL 202 CA NCBL.

S E E! LOCK CREfiCENDO AIR PUMP

REROLL PBpAL TREDLE v EXPRESS ION 140 1541 BOX Cilia mea BASS EX PRESS IO N BOX 16 192 Aug 7 s. H. PERRON REPRODUCING PIANO Filed July 12. 1921 9 Sheets-Sheet 2 Aug. 16, 1927. Y 1,639,105

s. H. PERRON' REPRODUCI NG PIANO Filed July 12. 1921 9 Sheets-Sheet 4 V/Ai/ Aug. 16, I S. H. PERRON REPRODUCING PIANO Filed July 12, 1921 9 Sheets-Sheet 5 CIi iQQQQQC i-Ll S. H. PERRON REPRODUCING PIANO Aug. 16 1927. 1,639,105

Filed July 12. 1921 9 Sheets-Sheet 1,639,105 Aug. 16, 1927. v H. N I

REPRODUCI NG P IANO Filed July 12, 1921 9 Sheets-Sheek $0 mag/Z7 22 Patented Aug. 16, 1927.

warren srarss' PATENT ()FFECE.

SAMUEL'H. PERRON, OF MENDON, MASSACHUSETTS, ASSIGNOR TO ALEXANDER STEINERT, OF BOSTON, PIASSACHUSETTS.

' rinrnonucme PIANO.

Application filed July 12, 1921. Serial No. 484,257.

This invention'relates to an automatic musicalinstrument of the type wherein a perforated note sheet or its equivalent is employed to govern the playing of the instrument, andhas particular reference to pianos which are now known as reproduc mg pianos. "A reproducing piano is one having the "c apa'ci ty of automatically and faithfully reproducing all of the characteristic shadings of the artistic performance of a skilled pianist. 'Thisis rendered possible because the reproducing piano is' equipped with expression mechanism which enables varying dynamic or intensity effects to be produced from pianissimo to fortissimoand also with mechanism producing theloud and soft,pedal effects, 'The note sheet for such a repro'ducing piano (in addition to having the necessary, note perforations for sounding the piano Y strings) has numerous expression holes which control the various expression devices. Also, the note sheet commonly equipped with a control hole to automatical ly bring into action the rewinding or're-roll mechanism after a composition. has been played. The reproducing p'iano' thus differs from the ordinary automatic'piano player 'or pla'yenpiano (controlled commonly by a note sheet with 88 -'per-for'ations for con trolling the 88 notes of an ordinary piano) in that it has'th'ese numerous additional expression devices governed by corresponding additional holesin the note sheet so as to reproduce the artistic renderings of a virtuoso.

A reproducing piano is usually, though not necessarily actuated or governed by pneumatic means and has a tracker formed with openings corresponding to the notes of the piano and which are adapted .to register with'perforations in thenote sheet as it travels over the tracker for the playing of the notes. In addition to the'note open- 'ings, the tracker has numerous other openings adapted to register withcorresponding additional perforations in the note sheet by which to govern the expression of the notes played by the piano and to effect other operations such as the re-roll of the note sheet afterithe composition -has been finished. iDiflerent; makes of reproducing pianos ferent makes do not govern the same expression and control devices. Accordingly, a note sheet prepared for use on a reproducing piano of a particular make will not play successfully on a different piano.

' aTllB purchaser of a particular make of piano, t-herefore, is limited in his selection of'music to the library of note sheets furnished for his piano; and he cannot satisfactorily use a note sheet of another manufacturer which is perforated in accordance with a different system.

The primary object of the present invention is to provide a reproducing piano with means by which it may be conditioned to play: successfully a plurality of different note sheets which are perforated for ex pression and control in accordance with different systems. The improved means are of such character that they may be conveniently applied to existing reproducing pianos.

In accordance with the present invention. the reproducing piano is provided with manually-operable means by which the piano may be adjusted to play different kinds of note sheets so that it may be set in one position to play one kind of note sheet, in a second position to play a second kind of note-sheet, in a third position to play a third kind of note sheet, etc.

The tracker of the improved piano has as many expression and control holes of suf- -ficient number and a) rooriate location to correspond and register with the expression and control perforations of all the different kinds of note sheets which can be played on the piano, and all of these holes which are not utilized in connection with any particular note sheet selected for playing are rendered ineffective and idle for the time being.

An improved construction and arrangement of expression and control apparatus is provided so as to enable the different kinds of note sheets to be successfully employed.

The present improvements are illustrated 1 the accompanying drawings, whereinthese letters, as well as by their designating slide valv'efshown in Fig. 9

numerals. This diagram illustrates the bass end of the tracker on a large scale and the pneuma ic connections therefrom to the various expression and controlling devices. Fig. 2 is a diagram illustrating in greater detail the portion of the apparatus utilized in playing with the C note sheets, other parts or the complete system being omitted. Fig. i; a diagram illustrating the portion of the -.-.pparatus which is utilized in playing with the other two note sheets A and B, other parts of the complete system being omitted. Fig. -1- is a diagram illustrating the positions of the expression and control holes in trackers heretofore used in connection with the three note sheets respectively and in the improved universal tracker used in connection with all of said sheets. Fig. 5 is a front view partly broken away of the s 601 box of the iano. Fi 6 is a trans ve'rs'e srection taken through the tracker and illnstrrtiag inure particularly the means for selectingthe proper expression and control holes-(. fthe tracker to correspondith the "Lu'ficulari'note sheet-to 'he'played. Fig. 7 isa plan detail of the selector valve'hoxes. Fig. 7. i's'a longitudinal sectionthrough a pa'it'of one of the selectpr valve boxes. Fig. 8' is. an "end' vievt" ofthe manually-operable i selector "control- Fig; 9 is a transverse sectionithr 'z'gh the tracker-laud the mnsic'and talre' 'np rolls. *Hh s'trating" a" modified form of selector; Figl' Q9 detailed .view 1 illus- Ttrating theari'zing'erii'en of-d'nctsinthe v p -Fig. '10 is a plan i i'en fof the iniproved e'zipressron boxes. F a'"vie\v'-similar- 5d 10 with the,to'p Qatari-airmail; Figi 12 'is' a vertial"seicti6ii of the eipresioni hones' in the plane indicated by the"1i 12- -'12 in 11 Fig; 1 jsidevieiv of th"expression hp es from the point of view indicateaby the lineli313firiF-igi 12 ."a '-por tion of th'e side .vv'al-I being removed to ex'pos'e-"theintensit'y expressionf valvesl Fig. 14 is a see- I 'ti'on'jn the plane indicatedlbyfthe-liiie 1414 in Fig; l2. Fig. Iii-is a 'plan view of 'fa may valve b0.\.' Fig. l6 is, a-section in the plane indicated by tne line 1 6' 16'in Fig. 15. Fig. 17 isa section similar'to-tha-tof' Figi 16': but the va'lvefin raised position. Fig.

18 is tiflongitiidinal sect-ion in the plane indi'cated by the line 18-18 in'Fig. 1-9, illustrating a crescendo pneumatic ns'ed'in connection with the C note sheet. Fig.19i's 'a'cr 'c-section iirthe plane indicated by the line 19-49 in Fig. 18. Fig. 20 is a frontyien of the loelrand cancel valve box which is used in connection with the C note sheet. 21 isa bottom view of the lock ce valve box. 22 is a cross in'tlie plane indicated by the line jl i 0. Fig. 23 is-a cross-section ..dicated by the line 2823 in junction no; used in the cancellation or clos ing of the valves in the box shown in Fig. 20. Fig. is a longitudinal section of the portion of the relay valves illustrated in Fig. 15, the section being taken in the plane indicated by the line 2525 in Fig. 15.

The pianos on which the several note sheets are used have pneumatic actions in their self-playing departments, and in each instance the air in the various Wind chests is under a partial vacuum produced by an air pump. Accordingly, in the illustrated embodiment of the present universal system the air is maintained under a partial vacuum by the air pump 200 indicated in Figs. 1, 2 and 3.

In all of the instruments using-the three designated notesheets, the expression is in part controlled by varying the degree of suction in the wind chests which supply mo- 'sionfholesin; the: nteisheetsna in, the tracker automatically c'ontrolirtihe' mechanism which is governed-byaiihevlpud aI rd-sofi pedals of the pianmsosas to v ihrati ono f the struck? strings-onto softentheione." .1

.A1so-,--in-a.l1 threemfthese pianos there is an a perturein 1 the tracker controlled by. a correspondingxeperture .in .the note ,she et which results in the automatic rewindipg or re-rolling 'ofthe; -note; sheet gaiter the composition thereof? has been completed.

andB sheetsrespectiyzelyialso have apertures int-he tracker controlled-by.- corresponding fapertn res in the. note -sheet-hy which ,ihe theme -.';Two of these pianospsing the A- 'no tes'are'. trcce'ntodiin'hoth the and treble sectionsofthe pianogf D :r-The; third: piano is characterized by .tyyo

features which-are not employed imthe other two? pianos: The-piano using. the. :C-shet has aicrescendo devicevvhich can-act quickly or slowly, depending upon which one ,of two 'holesinthe' trackeris uncovered by apertnres in the note sheet. Also, this piano is further characterized by certain so-called lock and Pcincel -,val-v.es governed by special holes in-blue tracker at both the 'bassand treble ends :by uneans of.-whicl i -when any M 15;. 2t is a sectional detail of a tracker hole is uncovered which governs one of the intensity pneumaticvalves the corre-- a special arrangement iofptracker .holes fc? producing the foregoing resultwliich differs form that of either of-theother two pianos.

Accordingly, itis apparent. ,tha t.no .one of the stated .note sheets can be successfully used on any. piano except the oneior which it is specially prepared-r In accordance with. he a universal reproducing piano is {presented upon ;which ;all three of the specified note sheets can be; successfully l d The improveduniversal reproducing piano has a novel; universal .tracker capable of cooperating wit-hall three :Ofthe specified note sheets; a selector which is adjustable to cooperate in turn with any oneof thethree note sheets; and cooperating expression and-con trol devices so organizedas to .cooperate with the several note sheets inturn.

- The several features of the improved piano will be described underappropriate .headproved ,universal .tra cker -D,- has note .holes 31, adapted-to register with. the apertures in the note sheet which control the ik neumatics-and at each end.it.has.a group of additional expression and: control .holes 32.. Fig. talsoshows at A,. B and C, trackers for the A, B and C note sheets respectively, and it will be noted that the three differ from each other so far as the expression and control holes are concerned. It will also be noted that the universal tracker D, has expression and control holes corresponding in number and location with all the expression and control holes of the three trackers of the indicated pianos.

in Fig. l which shows the group of expression and control holes at the bass end 01" the universal tracker D, these holes are designated by the letters a to is inclusive. Of these holes, j and 7c are used for expression purposes only when the A note sheet is employed. Hole a is used only when the 13 note sheet is employed; Holes e and g are used only when the C note sheet is employed; Ofthe remaining holes-only dandh are used for the same purpose with all three note sheets.

In-the pianofusing the A sheet the fourv holes h,-i, j and k; are used to control the intensity of the suction in the wind chests.

pedal. Hole b is used to control the re-roll.

In this piano the expression holes h, i, j, k, are alongside note holes which are inoperative when the expression holes are used, and are brought into action. when an ordinary unexpressive 88 note sheet is employed.

ln the piano usin the B sheet, the tracker hoies (l, f, h and z'fhave the same offices as the corresponding holes in the piano using the A sheet. 7 In addition, the piano using the B sheet utilizes the tracker hole a'to control the intensity of. the degree ofsuction in the bass \vind chestitra'cker hole I; governs intensity; and trackerholec, controls the re-roll.

'In thepiano using the C. sheet, the tracker hole's ,.c, e and It control" the intensity.

Tracker hole i cancels. the "intensity control valves. Tracker holes- I and 37 5 govern the slow and fast 'cr'es'ceridos respectively.

Tracker hole d controls the l 'd 'p'eddll;

:this piano the r e{r oll governed-by "hole 1) Fig. 4) at thetreble end of'the tracker.

Similarly, the expression and cohti'olIioIeS at the treble-end ofthe tracker differ in arrangement in these three pianos. From this statemlnt it pparent' that some special instrumentalities must b'e' employedto enable all three note'sheets be success-fully used on the same piano.

SeZect01.-Tl 1is capacity forcondit-ioning the P o to ip aya ths ffih e .9fihe f nate'd note sheets 'res'ults'j'fromf theselector devices which areeniployed: f

' There are as many selector valve boxes as there are note sheets playable. In the prei'ent case,.three such boxes: 33, '34 and 35 are shown. As indicated'in Fig. 1, the

'selector valve box 33- is active when an A note sheet is employ-ed, the box 34 is active when a B note sheet is employed. and the box 35 is active when a C note sheet is crnployed. I

The construction of these selector boxes is best shown in Figs. 6, 7 and 7*. Each box has a. wind chamber 37 which adapted to be put into operative connnunn cation with the suction side of the air pump by the selector controlshownin Figs. (3 and 8. Each selector valv'e box has at one side a series of compartments each constituted by a. conical valve seat 36 (a shown in Fig. 7') which is separated from the wind cham- 1. JIFFY 'ber 37 by means'of a pneumatic valve 38.

Each of these pneumatic valves 'isconstitntcd by a flexible diaphragm or pouch which entirely surrounds-and covers the corresponding compartmcnt and valve seat 36 and isolates it from the wind chamber. There are as many of these'valve seats and pneumatic valves for each selector box as there are expression and control holes in the tracker for each corresponding variety of notesheet Fig. T is a lo nqitudinal section through the upper selector b03133, andthe cooperating valve seats are designated by the numeral 36. The valve seats for the lower box 34 are indicated in Fig. (Shy the reference numeral 3.61"; and the valve seats for the intermediate box 35 are indicated in Fig. 6 by the reference numeral 36".

Each pneumatic valve 38 controls the pas sage of air from a duct or pipe leading thereto from a hole in the tracker to :1 duct or pipe governing the particular expression or control device controlled by that tracker hole. A description of one pair of ducts pipes and the corresponding pneumatic valve will suffice for allf As shown in Fig. 6 a duct 48 leads from one hole. in the tracker to the base of the corresponding compartnientbetween the conical valve seat 36 and the valve 38. second duct 39 leads from the apex of the conical. valve seat 36 to .control the corresponding expression or control device.

Normally. each outgoing duct 39 is: clo--ed andsealedby the corresponding valve 38 so that tliere is no passage of air from duct 48 to duct 3.9. Also, normally, the wind chamber 37 isvented to the atmosphere, as

descrihed hereinafter under the heading lector Control so that the valves 38 are main tained their duct closing positions by he pi rtial.'achum ormally in the ducts when the piano is automat cally"played.

If,.l iq vever thewind chamber 37 of one ofthe selector bgxesslitguldheput into communication with th'e suction side of the air pump, asis shown to he the case with the middle box 351 in -'F ig. 6, .then all of the valves 38 Within 'tha t borwill be drawn away from theirse ats', as there shown (due to thegreat area of a valve as compared with thatpttheeduct- "closed it) therebv putting t h e" d1 1 ct s'. oi each pair in communication with each other. Accordingly, if a hole in the tracker which is in commimjcation with the compartmept; of an open valve 38 .is then uncovered a corresponding aperture inthe note sheet both ducts of the pair will be vented to the atmosphere and the-control or expression devicej governed thereby will be brought into action. 7

In thc drawings, the ducts or passages which lead from the tracker to the A box 33 are designated by numerals 48. 48. 48", etc.;;an d the pipes extendingfroni this box are-designated as 39 39;, 3. 9", etc.; and from these pipes lead tubes or ducts 42, 42 42". etc.

The ducts which lead from the tracker to the B selector box 34 are designated by numerals 49', 493, 49", etc: and the pipes leading from this box are indicated by the numeral 40, from which extend the tubes or ducts 43, 43, 43", etc. i

Similarly, the ducts leading from the tracker to the C selector box 135 are designated by the numerals 5O, 50?, 50 etc; alid the pipes extending therefrom are indicated 'by the numeral 41 from which extend ducts or tubes 44. 44, 44", etc.

Since the pipes 39, 39. 39 and 41 are ordinary mechanical cxpedients for the attachment of the tubes leading therefrom, they are omitted from the diagrammatic Fig. l.

It has already been pointed out that some of the holes in the tracker are used for all three note sheets, and in other instances some of the tracker holes are used with two or more of the varieties of note sheets. In such instances the duct leading from such a hole in the tracker is branched so as to communicate with more than one of the expression boxes. Take, for example, the tracker hole (1. shown in Fig. 1, which is common to all three note sheets and which acts when exposed to control the loud pedal in each case. As shown in Fig. 1, theduct leading from this hole (I, has three branches, one branch 49 leading to the B expression box; a second branch 50 leadingto'the C expression boxjand a third branch 48 'leading to the A expression box.

Similarly, it will be noted from Fig. 1, that each duct leading from each of the tracker holes b, c, and "-f, has two branches; and each duct leading from each of the tracker holes h and 'i has three branches.

Selector control.-In order to play with a particular-note sheet it is necessary that its" corresponding selector valve box jshould be put into communication with thesnction side of the ainpum'p' and that the other selector valvc boxes should bdveritejdftd the open air.f This' r'esiilt is achievedby'amanuallv operated selector control? shown best in F san A. slidevalve 54 is valve" block 52 and is. maintained in -'an adjustedposition bya fiat-leaf spring- L, as shown in 6. Thisvalve block is connected by a link't34 with a' handlever 63. The upper 'end' o f hand lever constitutes an index finger cooperating with the appropriate note sheet designations A, B, andC; andwhen the hand lever is moved by the user so that the indexfinger points to one of these letters, the sele'ctor will be properly -adj usted'so that the corresponding :note sheet can'be played. The" valve block hasthreje du'cts, 55, 56and 57., in' li n'e'with each other which extendfrom the (interface 5r the'valve' block to' the seat 53 against which the valve 54 slides." The duct 55 communicates through the pipe' 58 With the A selector box '33. 4 The duct 56 communicates through the pipe 59 with the B selector'box 34. The duct 57 communicates through the pipe 60' with the C selector;b0x'35.

The slide valve has a, duct 61 (-Fig. 8) extending entirely -across it in the plane of (th hr e sauce 55, 56"and 57(This va-1w 3 10:; mounted to slide'in a' duct 61 communicates through a flexible pipe 62 with=the suction side of the air pump 200;, as shownjiii' Eigsz' l Q. and"33.5 By sliding-= thefvalve;54l.any zone-10f .the diicts 55,

56and 57 cant-be registered-with;theduet Lil, and; accordingly; the wind .-cha-mber 2) i .any one of=the selector-1 :boiicseanibe brought into communication a-with-J thei air. pmnp'i .As shownin: Eigs 1;. thmhanclilevr =63-. is in its intermediate positioncpointing .-C,- and when .in tliis'i-positionethers lid wai e d 61 ='registers:svith:-a;th intermediate duct; 57 oi othegwalve ublock rzandi-zoonseili e lflyi chamber 3 5 of-thei-Qselectpr, bog 3515 Tin1'bemmunicatiomsvith'Etheisuotion side of themix; puinpryithgtheq-resulmthat a1 l,o f; ,the eommimichtin' sv'alvesh38;.l are eo'peped and the zapertiires an the :6 note; .sheegean -.th e n control theaetfon-iot-theexpression: andgeon- 2o tmlfdevibesaiimi afil .(.:'l.-.- ;.-i;-.-. 5.; thistfininrlnedijatle'nlpositioni:shown? in Figt'i 6;!th'. dther fiwdjseleeto'ri :hoxes .33 and 34Q1rei vented :tohthe open; air by of two lpngitudinah channels 54min, the ;face; of 1 #t'he slide vaglve'vadjoiningi the ivlalvfe seat 53.

f Aecordingly tlies'e'selecton boxes; are;. r nain- -tainediidlei'ande inactivewhilmtlfe (I note sh'e'et evil-:1 si'ii is, a Ifitliedranfl lei'renii's moved (so asippin '-t their thelright'ehand venting cl 1 a-x 1 nel gM will ooxnniinhca-te-mivith:bothii llfltSzs56 --dnd hamme -11mm lboth hogres audflssqmsimilarly ijzthe hmt le er is as: hand bhanhehbi in the; :valve seat will com- "iiiimicate .withzboth. ducts fand 57,,gnd the JtivoRxs|33wand135wi 1 beiw d .i f::-1ReZw3 s.+As;indichted:in.Eigiil; the p p I extendiug' frdmsthe i-s'ele etor valve ;boxes do 40 not lead directly :to. .the LexpressionQahdponother .pipc slead-.to. theyexpression and control devices. All oi. the relay; valves are alike so t-hatit suliicesto refer to a single relay {valve siich =us=is specifically shown in Figs. 15, 16 and 17. .1 1

The relay-box159, shown in these figures has a wind chamber 161 which is in coustant-com munication with the suction side of the :airpump through the pipe E. Above the avindthambenlfil. is a serieso'f valves 164, each locatedZ in its own valve compartment 162;- From this-valve compartment extends: a pipe" to the corresponding; expression or control device-to ;be governed by the particular valve 3In-...-Fig.;-16-, the

particular pipe lz'it'indicatedflis the one.-

inch leads to the -accent pneumatic 8S gs- 1 and l4).- v

thevalve chamber 162't0the open air. gNormally,- the valve 164 is in itszposition shown in Fig. 16, opening the vent 165 and closing the passage beneath. to the-wind chamber 161. -The correspondingexpnfsion or con- 4 tire ducts leading trol .devices, but lead-eto-relays from ;whieh bet ltil.

- Above the valve lfi'is vent 165 from trol device, such as the accent pneumatic S is hence'nori'i'ially vent-ed to the atmosphere.

Below the wind chamber 161 is a series of compartments one for each of the'cxprcssien or control devices. Each chamber 160 has an Oiflflliilf :zt its top which is closed bye weighted flexible diaphragm or pouch 163 which on its npper'side is exposed to the suction within the. wind chamber 161; This peach isimn'iediately benea th the stem'of the valve 164.. A minute bleed'duct- F, establishes a permanent. connection between t he wind chamber 161 and thefcoinpartmcnt160. Each compartment. 160 communicates with one of the selector boxes. In the'partichlar instance'shown in Figs. 1 6 and 17, the chamher 160 oommuiiicatesbypipe 42fjwitho-ne of the duets in the Aselectorbox-33 and through a branch pipe {1-3" with one of the ducts in the B selector b0,\'.3 i f1 Assuming-thatgthe A noteIsheet should-be in use thenthere would be a'continuous passage from .the tracker hole-f through' the .pipes .48 andA2", as sliown'in Fig. 1, tothe compartment 160, shown Eigs. 16' and 17.

.As long as the trackerlholej isclo sed bythe note sheet, there is a partialvacuumiii these pipes by reason of the bleed-F, between the .wind chamber 161 and the eompartmehtl'GO.

.Accordingly the weighted pouch 163 having .equal air pressures'abo've andilielow is main- -.tained by gravity .in the pofsfliti'ongsliownfin .Fig. 16 andthe valve 164 is in its down position, closing .comniunicati on betwee h' the wind chamber 161 and the compartment 162 and venting. that compartmentto the open 1111'. .Hence, the normal'condition being that ;\vhen the tracker h'oles are closed by the note sheetQ-there is normal suction in the then acfrom the tracker..

'hen, however a hole in the tracker'is uncovered by the note sheet say the hole f. then the duct. leading; from that hole is vented to the. open air and the pressure in the correspomiing: compartment- 130 l6 rises rapidly in ntnispheric pr: '11 so that the 'n'essurc. in the cosnpartun-sit 1G0 becomes greater than that in the suction wind cham- Accordingl g the pouch 16 is ins =i|1ta n-.(nzsl raised to the position shown in Fig. 17, thereby lifting the valve ltial so as to close the rent 16:? and to put the valve coin- :-artincnt 162 into comninnication with the wind chan'ibcr itil whercupon air is sucked through pipe 154 reducing the air pressure therein and bringing into action the particu lar device (accent pneilmatic 88) controlled by such pipe 154.

As soon as the traveling note sheet again covers the tracker hole 1, the corresponding compartment 160 shown in Fig. 17, being no longer ventcdto the open air, has its pressure reduced through the bleed F, thus again equalizingthe pressure in chamber 160 and con'ipartinent 161. Tliereupon, the weighted lOO pouch 163 drops to the position shown in Fig. 10 and the valve 164 drops both owing to its weight and the excess air pressure on its upper side, thereby again venting pipe 154 to the open air and hence restoring the device 88 controlled by pipe 154 to its normal position.

These relay valves respond quickly to the smallflow of air through the tracker holes and permit larger passages to be employed leading to the expression and control devices, thus insuring their quick response in accordance with the customary oi'rice of relay 'va1yes.,

Therelay box 159, as shown in Fig. 1, has seven relay valves, only four of which are shown in Fig. 2 since they suiiice "to illustrate the characteristics peculiar to the mechanism employed when the C sheet is used. Special relay b'okes 2 01 and 203 are also shown in 1 and 2 which are peculiar to the C no'tesheet mechanism and their relay valves are constructed and'ppera'ted in the same way as thei'elayi'valves of the relay box 159. R -z-oll'jmd pedals-The holed-in the t racker -co'n trdls 'the loud pedal for all three notefsheetisl. a sheen in Fig. 1, the, "pipe 13? leads 'from the B 150x34 to the relay 159, and it ,c brr 'es'pdndi'rig 'pi'pe leading from the re l hy extend to the device for controlling .Tlie iparticular devices for controlli'ng the 10 d are iiot shown in the acc'oihpanying clr awiiifgsb'ecaiise ordifiary devices are fl i pl'oye'd having no nov- Tefltyx pipe-ili2f1leading'frdm the "A selector 5.6x ki t f fifli i l ua ets Wi -t p n h ni-a F -.1; a are h i m loud pedal-60mm; is governed when the A sheet .isemployedQ p'ip'e l if leads-equine C seie tpr box to the pigeaaeganu hence contro'lsthe lo'iid pedal. lhe pedal effects hegemnpa ffro'rn'th'e treble end of the tracker when using any one of tlie desigf i ddfli lshe s, lfhetracker liolec 'shown in 1, contiol sl'thejrefrdll when theB sheet-is 'em 'pIoy'ed, Bipe 49 leads 'f1'om' 'tracker -hole c to the B selector box '34; pipe 43 leads thence to the. relay 1,59 and a pipe leads from the relay to the devic'esrwhich e'flectthe re-roll. These {devices are we ll'knownand are not shown in the drawings.

7. Similarly, bra-rich 48 .leads from tracker hole 6 to the A selector box 33 and rom thence pipe 42 leads to and communicates with pipe 43 and "hence controls the ire-roll.

The regroll connections when the 'C note sheet; is'used are'not'sliown in'Fig. 1 because that figure shows 'oii'ly the devices controlled T from the bass end of the trackerand in the piano using the C sheet the re roll is controlled by a hole Z (Fig. 4) at the treble end of'the tracker.

Expression bo w.The expression pipes from the A and B selector boxes lead to the relay 150, as shown in Figs 1 and 3, and from this relay corresponding pipes lead to the expression boxes and 81. These expression boxes are shown in detail in Figs. 10, 11, 12, i3 and 14. They are herein called bass and treble because they are controlled from holes at the bass and treble ends respectively of the tracker.

The bass expression box 80 has a wind chamber 96, shown in Figs. 11 and 12, which is in constant communication through pipe 97 with the suction side of the air pump 200, as shown in Figs. 1, 2 and 3, so that, when the piano is playing, a partial vacuum is constantly maintained in the chamber 96. This compartment has an outlet 101, shown in Fig. 12, which is controlled by a swinging knife valve 100. This knife valve is connected with aregulating pneumatic '99, (Fig.

13) the movable board of which is underthe stress of a spring G, which tends toopen the valve in opposition to. thepartial vacuum maintained in the variablepressure compartment 98 into which the outlet-101 opens. The tension- 0f this spring G is adjustable so that the valve 100*partly closes the outlet 101 and thereby determines the normal degrees ofl-j'suction in the strikerpneumatic wind chests, this pressure being that employed to produce the pianissimo effeet. As shown in Fig. 12, the compartment 98 communicates a t all- -times with a chamber 102 which is in communication through passage 103- witha compartment 82 .in the treble expression box 81, as shown in Fig. 11, and from the. upper end of this compartment 82 a-pip'e 84' (Fig; 14) leads tot-he usual bass wind chest ('not shown) for the strikerpneumatics. Likewise,.as shown in F-ig'.--1'1, the chamber 102 communicates through. pipe 104 with a compartment 83 in thetreble expression box 81; and, as shown in Figs. 10

and 14, this compartment 83 communicates through pipe 85 with the usualtre'ble w ind "chest (not shown). for the striker ,p'neumatics. y

Each of the passages-103 and 104 "at, its

'suction side is covered-by a swingingcheck valve 105 located in the compartment 102, as shown in- Fig. 12. These check valves open freely in response to suction in the compartment 102so that they do not intertere with the creation of suction in the bass and treble wind chests produced in the vac uum chamber-96'. But, in the event that a 'greaterdegree of vacuum or suction is created in one of the compartments-82 or 83 "o'f the treble expression box as compared with the suction in the compartment 102, the corresponding check valve 105 closes and the greater degree of suction in such compartment 82 or 83 is not reduced by the lower suction whichmay then be in ment 102.

the comparttil) wind chamber 96 (seeFig. 12) than is per mitted by the valve controlled outlet 101.

Provision is' made for by-passing at'tour diiferentl places the suction from the chamber 96 to the compartment 98 and thence to the chamber 102 around'the outlet 101 and the valve 100; -'One ofjthese by-passes is shown' in Fig, 12, wherein" a "duct128 is shown leading from 'thechamber 96 to a channel 115',shown also in Fig. 13. 'Th'eca paci'ty of this duct 12 8 can be regulated by an adjusting screw 132 grim outlet from thisduct 1.28 to thef channel 1115 is normally closed by a pouchcr' diaphragm valve-136. The compartment 144 at the iddf -thi's' valve opposite the passage 128 .commimi cates' with I a. pipe 140; and this i particular pipe, as shown in Fig. 1, extends to one of the relay valvesin the relay box 159, and'is controlled by'th'e tracker hole I) when the B note'sheet' is used, by the tracker. holec when the "Quote sheet is used,..and by the tracker hole 11 when the 'A note sheet is used. Owing to the relay construction, shown in Figs. 16 and 17, the pipe 140 isn'ormally 'ventedto the open air so that there 'is"atinospheri' c P r n her aaemslexr e and as thefother -ornner;r1ght hand sidefof the pouchvalve is exposed to lower pressure it is normally maintainedin the position shown in Fig. 12, closing the duct 128.

When, however, a corresponding expression. hole -in the tracker is opened, then through the action of the relay valve suction is created in the compartment 144, at the outer left hand face of the pouch valve 136 and the duct 128 is opened. Suction is thus created in the channel 115 and a light check valve 124 (Figs. 12 and 13) in the channel opens, thereby uncovering a duct 120 leading from channel 115 to the compartment 98. Accordingly, increased suction is then created in compartment- 98, chamber 102, compartments 82 and 83 (Fig. 14), pipes 84 and 85 and the bass and treble wind chests of the striker pneumatics. As the result there is a greater intensity of suction in the wind chests and each of the striker pneumatics then brought into action by the note sheet produces a more powerful blow upon the corresponding piano strings.

There are four such by-pass ducts leading from the vacuum chamber 96 to corresponding channels and thence through as many valved ducts similar to the duct'12O to the compartment 98. Fig. 13 shows two of these channels, 114 and 115 respectively: two of the by-pass ducts 127 and 128; and two of the ducts 119 and 120, leading to the compartment 98, closed respectively by hinged check valves 23 and 124.

Each of the four by-pass ducts from the vacuum chamber 96 is controlled by its own pouch valve, similar to the valve 136 shown in Fig. 12,- and correspondingly there are four pipes leading therefrom to tour of the relay valves, asshown in Fig. 1, and thence to correspondingholes in the tracker for the three'note sheets.

These four-pneumatic pouch valves con stitute intensity" or dynamic Pneumatics. when all four of' these intensity pneumatic valves are-opened concurrently the maximum degree of suction is created in the wind chests for the striker-pneumatics, and the loudest-sound is produced. By appropriate location oftheholes'in'the-note sheet any number of the by-p'ass communications from the vacuumbr windehamber 96 (Fig. 12) to the wind chests can be opened, or all can be maintained c'losed' The relative capacity of tlie severalipassages can be "varied by the adj listing screws'131, 132, an'd the several passages 'can'be uncovered in variouspermutations by the; opening ofone or more of the controlling tracker holes. Thus provision is i made fora large range in'the force with which the-piano strings" may be struck by the'hammers. I

In'the'arrange'm'ent shown in Fig. l, the four inte nsity Pneumatics bfthe bass expression box'are controlled'respectively by thet-racker: liole's I1l," 'i, j"-;and k;'when the A note sheet is employed:

lVhen the 'B note 'she't is employed, these four intensity pneumati'cs 'arecontrolled by the tracker holes a, b, h and i When the note'sheet employed only three of the intensity"pneumatics are controlled, and tracker holes 0, e and h are utilized for this purpose.

The treble expression box 81 has a vacuum \vind chamber 94 (Fig. 12) which is in constant communication with the vacuum chamber 96 through the connecting pipe 95 (Fig. 11) and hence in constant communication with the suction side of the. air pump. lhis vacuum chamber 94 has an outlet 92 into a compartment 90 and this outlet is partly closed by a regulating knife valve 93 connected with the movable board 91 of a There is an important difference, however,

Also, there are four bybetween the treble expression box and the bass expression box. As already pointed out the variable pressure chamber 102 in the bass expression box communicates directly with both compartments 82 and 83 in the treble expression box, thereby varying the degree of vacuum in the treble wind chest as well as in the bass wind chest. But in the case of the treble expression box there is no constantly open communication be tween the chamber and the compartments S2 and 83, since the communicatingports thereto are normally closed by valves 86 and 87, as shown in Fig. 14. In order, therefore, that theregulating valve and the intensity pneui'natics of the treble expression box shall be eifective it is necessary that one or both of the valves 86 and 87 should be opened.

The valve 86 which is located in the compartment 82 communicating with the bass wind chest through pipe 84 is controlled by a pneumatic 88. This pneumatic 88' communicates by pipe 1 54 (see Fig. 1) .with a relay valve inthe relay lotl and is governed by tracker hole 7 at the bass end ofthe tracker when eitherthe A 01:13 note sheet is used. This accent or theme pneumatic S8 is not used when the C note sheet is employed.

Accordingly, .whena particular notein the bass isto be acoented,-.-the .trackei: hole is uncovered and, as ,the res ult,'.-a partialvacuum is created withirr thegacgentpneumatic S8 whereupon it col1apses',;itsmovab1e board moves upward, the valve,86 ig. 14). is opened, and the vacuum jn 'tlie. bas s wind chest is augmented by thgfidditiona l-suetion from. chamber 94, through port 93 ahdpast valve 92, into compartmen 2, thus accenting the note. ,f I p;

In thisconnection, it will be-iioted, that the vacuum in; the compartment v82: due to the opening of the valve 86:.is not reduced as the result of a concurrently-lesser vacuum in the compartment" 102 because in such case the check valve- (shown in Fig. ,12) closes the passage from compartment 102 to compartment 8 If, concurrently, intensity "pneumatics (one or more) of the treble expression box have been opened there will. be a correspondingly greater suction the compartment 82 and hence in the bass wind chest, thereby variably accenting. the particular bass note .or notes then brought into action by the note sheet. When tracker hole is again covered atmospheric pressure enters the pneumatic 88, equalizingits internal andex-ternal pressures, whereupon the pneumatic distends by gravity aided by suction on the valve 86, and said valve closes.

Correspondingly, the valve 87 which governs the communication between chamber 90 and compartment 83 (Fig. 1 1) in the treble expression box is connected with the movby apertures in.the

able board of an flCCUili or theme pneumatic 85), the interior of which communicates through a pipe 155 to a relay valve and thence to an expression hole at the treble end of the tracker. opened the accent pneumatic 89 will collapse, the valve 87 will open and an increased degree of vacuum will be produced in the treble wind chest depending upon how many of the intensity pneumatics of the treble expression box are concurrently opened by corresponding holes in the note sheet.

Here it will again be noted'that the check valve 105 (see Fig. 12) automatically closes in the event that the vacuum in compartmcnt are four such regulating neumatics 150, 151, 1

152 and 153 forthe treble'expres'sion box, one for, each of the intensity Pneumatics. The constructionof these neumatics is shown in F 12. As there shown, the interior of pneumatic 108 communicates through a port 118 with the channel 115 and the outer movable board of thepneuinatiC is pulled upon an adjustable spring 112. This pneu- .matic collapsesto theextentpermitted by its regulating'spring when the by-'p'a'ss' duct 128 "is opened.- In case a' chord of many notes is struck" thus consuming a large volume of air and tending to reduce the degree of vacuum in the wind chest, the regulating pneumatics thenin action expand and substantially maintain the dcgre'e'of vacuum.

\Vhen the valve 136 again closes the duct 128, the spring 112 moves the movable board of the pneumatic outwardly thus nuunta1n ing a partial vacuum in'the channel 115 and taking care of leakage.

These regulating Pneumatics are not essential and may be omitted. .Loclcand caneel 'vaZ't-cs.' he piano using the C note sheet differs from the pianos using the A and B not-e sheets in that it has certain "alves which are locked in open position as the result of the note sheet uncovering certain expression holes and they remain open until cancelled by a subsequent perforation in the note sheet uncovering a particular control hole in the tracker. l

The present improved piano includes lock and cancel valves which are utilized only when the C note sheet is employed. This Hence, when that hole is H iii] lock and cancel valve mechanism for the bass is indicated in Fig. 1 and Fig. 2 and is shown in detail in Figs. 20 and 24 inclusive.

There are three of these valves 167 each centrally pivoted at 168 to a valve block 169. Each valve swings across the valve seat face 169* of the valve block. Each valve controls a duct 171 in the valve block. From these three ducts 171 lead pipes N extending to the relay 159 (Figs. 1 and 2) and through the relay control three ofthe intensity pneumatics of the bass expression box. This mechanism is duplicated for the treble.

Normally, the valves 167 are in position to close the ducts 171, as shown in the case of the two valvesat the/left in Fig. 20. Each valveis acted upon ,by two pneumatics 172 and 174 located at opposite sides of the pivot 168 of the valve. The pneumatic 172 acts to open the valve, while the other pneumatic 174'acts to, close it. As shown in Fig. 22, the opening pneumatic 172 which is normally expanded by a spring R has a striker 173 on its movable board which is located in the plane of the valve.

The pipes M,'M, leading from the pneumatics 172 and 174 do not lead'directly to the C selector valve box, but lead-to a relay 201, the construction of which is exactly like that of the relay 159 heretofore described. ,From relay 201, as, shown in Figs. 1 and 2,e xtend the pipes 44, etcl', leading to the C selector valve box.

When a corresponding tracker opening is uncovered by an aperture in the :note sheet (namely, one of the tracker holes a, e or h) the action of the intervening relay 201 (Figs. 1 and 2) is to create suction within the interior of the corresponding pneumatic 172, whereupon its movable board collapses, its striker 173 hits the valve 167 at one side of its pivot, thereby swinging the valve to the position shown at the right in Fig. 20, and venting the passage 171; and, hence, through a pipe N (Figsf l, 2 and 22) to the relay 159, opening the corresponding intensity pneumatic valve.

The valve 167 remains in this open position after the aperture in the note sheet has again closed the controlling tracker hole and after the opening pneumatic 172 has again been expanded by its spring. The valve 167 is substantially locked in this open position as the result of the friction due to the spring 170 (Fig. 23) surrounding its pivot 168.

The valve remains open until its closing pneumatic 174 is collapsed. This closing pneumatic 174 under the action of a spring 8 normally stands in the expanded condition shown in Fig. 23 and it hasa striker 175 in the plane of the corresponding valve 167, but located on the opposite side of the pivot 168 from the location of the striker 173 of the corresponding opening pneumatic.

All of the closing pneumatics 174 for all of the lock and cancel valves 167 are controlled by the same hole 2' in the tracker. )Vhen this hole 2' is uncovered by an aperture in the note sheet the action, through the relay 201, to create suction in a pipe 1, Figs. 1 and 2, leading to a junction box 202 (Figs. 2 and 24) from whence pipes p lead to the closing pneumatics 174 for the three valves. As the result of the suction thus created within the closing pneumatics 174 they are all collapsed and whichever of the strikers 1'75 finds a valve 167 in its path it swings that valve so as to close the corresponding vent; 171. Accordingly, the corresponding intensity valves which are then open are closed.

Crescendo mecizanism.1n the piano using the C note sheet crescendos are employed as apart of the expression system and are shown in Figs. 18 and 19. There are two crescendos, one for the bass and one for the treble. -The crescendo mechanism includes a box 180 upon which the governing pneumatics 191 are mounted and this box has a vacuum wind chamber 185 in constant communication through pipe 186 (Figs. 1 and 2) with the suction side of the air pump. Associated with this Wind chamber are two compartments 181 and 182, (Fig. 19) connecting respectively with the wind chamber 185 by the passages 183 and 184. The compartment 181 communicates through pipe 187 with the base compartment 82 (Fig. 14) of the treble expression box. The pipe 187 is broken away in Fig. 2. Its connection with the compartment 82 is indicated in Fig.' 1. The compartment 182 communicates through the pipe 188 (Figs. 1 and 2) with the treble compartment 83 of the treble expression box.

Slide valves 189 and 190 are located within the respective compartments 181 and 182 and control the respective passages 183 and 184. Each valve is maintained against its seat by a spring J.

Each valve is connected by a link K, with a corresponding pneumatic 191. Normally, each pneumatic is fully distended by a spring 6, as shown in Fig. 18, in which position its connected valve closes the passage between the vacuum chamber 185 and the compartment in which the valve is located. 1 hen the pneumatic 191 coacting say with the bass is collapsed, its valve 189 is moved inwardly thereby uncovering the passage 183 and putting the chamber 181 and pipe 187 into communication with the vacuum chamber .185. Accordingly, additional vacuum is created in the bass compartment 82 (Fig. 14) with which the pipe 187 communicates, thereby increasing the degree or vacuum in the bass wind chest and hence increasing the intensity of any note which is concurrently brought .into action.

The valve 189 can be openedeither quickly or slowly, thereby producing either a fast or a ,slow crescendo elfect. The interior of each pneumatic 191 communicates (Fig. 18) with outwardly [extending pipes 192 and 193. l h e outlet 195 to the pipe 193 is partially closedljby an adjustable screw 194, thus chokin -tre outlet and permitting a slow flow oFairto and from the pneumatic 19L The outlet to the pipe 192 is not choked n cate with -tl1e,traelgerholes lgjand g. The

as; e the bgcontrpi u h 319w cresggndg PiPtlg-l" and h h le g c ntrols as first 9resendqpipe 19g,-

Provision is ma f rh util za 'qf...=. .-Q ".lfl. e' xp e sion an outr l h les Q the-Cmt she t a vel 'a r those of .fi is'l tf an 13mm shee s:

Q. iflb e-Fl 9 an his ia ea more form i .ie'ii ioimq iem m. is here sh ve; the nirssl ading m h xizr ssimi and n ol? 1 .12 of. he tracker l) 6 5 tor af slld'eya Tliis'valve -8.1. hree as of 'ap.-' f-iure respo innurnberjand location with the aper tures in the three note sheets. The uppermost row of ho es 69, 9' ,,-etc is'brought i "o' register with the pipes leading from Tue tracker when the B note sheet is em ployed, these apertures corresponding in lo-- cation with the tracker holes controlled by the finote-shect.

Likewise, the middle row of holes 71, 71 et corresponds in position and location with the tracker pipes utilized when the note sheet is employed.

The lowest-row of holes 70, etc, reg istcrs with the tracker pipes when the A h -di empl yed h ke 6. an e shifted to bring any one of these rows of 2 in o. r is ration w h th p p ead n hem-the tracker v m a of he ha eve 25 ll-$1 the. nter e iate '0JD-. .t.i0i,iS.- -m in.' ig- .9=- l c Erd' i L'th'QSe' ne ow Qt .191s. le -d pipe P7 and, H. ext ai ngit he ays n. thswe mi n r ii tlr caseei he pipes .3L finest-alre dyd scr bed ,th mamas: ;.o-p.e of; not slit ve. been missed. ta i the aux-nose o illestreti ngitis hr nas that-Wal et typ of note sheets maybe played by an arrangement of the expression and control holes in the tracker, and a corresponding group of selected expression and control holes.

The invention has been described as applied particularly to pianos, but itcan be applied to other instruments, such as organs wherein perforated rolls or the equivalent are employed to govern the playing-of the instrument. In the case of an organ, for example, the expression and control holes would govern the stops, couplers and swell shadeslof theorgan and also the rc-roll of the note sheet.

The invention has beer described as applied'to a musical instrument wherein pneuinatic means are employed to effect the playing thereof, but it is equally applicable to instruments employing other means to effect th .play n li -lain):

1, An expression system for a reproducing piano including a tracker having a plurality of expression holes, expression devices, aiid'means selectively to connect said expression devices operably \vitlrpredetermined combinations of expression holes, said means including a plurality of selector valve boxes all of which are connected with all of said expression devices and with predetermined combinations of expression holes, and means to selecta specific selector valve box for the control of said expression devices through its combination of expression holes.

An expression system for a reproducing piano including a tracker having a plurality of expression holes, expression dcvic and neansseIectiveIy to connect said expression devices opcrably with predetermined combinations of expression holes, including a plurality of selector valve boxes all of which areconuecied with all of said expres sion devices and h predetermine combinatio s of expix on holes. 'nd n inuallycontrolled means to select a pcrific SQiQiftul' alve ho for the control of said expression devices through its comljiinati n n1" oxprozl sion hole An expression system fora reproducing piano including a tracker having a plurality of expression holes, expre devices, and lnear" ;eiccti ve ly to con d o :p1cs dev operahly with predetermined COmbi IQti QS of liilc s on h es c u ng a plurality of selectorvalve boxes which are onnec ed' th l of 5 id exp ession de i and with predetermined combinations of expression "holes, and manuallycontrolled Dn mnat ei ean t se ec a pe ifi se t r l e, boy. fo he ontro aid. xpression de cesj l tough t com inat on of exp s on hol i An. esp ssio ystem. for r pr s Piano mending tracker having a Plurality e1 espresso}. hates; 'exnrsssion devic s, an

means selectively to connect said expression devices operably with predetermined combinations of expression holes, including a plurality of pneumatically-controlled selector valve boxes which are connected with all of said expression devices and with predetermined combinations of expression holes, and means to select a specific selector valve box for the control of said expression devices through its combination of expression holes comprising a valve associated with all of said selector valve boxes arranged selectively to connect said selector valve boxes to a source of suction pressure.

5. An expression system for a reproducing piano including a tracker having a plurality of expression holes, expression devices, and means selectively to connect said expression devices operably with predetermined combinations of expression holes including a plurality of pneumatically-controlled selector valve boxes which are connected with all of said expression devices and with predetermined combinations of ex pression holes, and means to select a specific selector valve box for the control of said expression devices through its combination of expression holes comprising a valve associated with all of said selector valve boxes arranged to select an individual selector valve box for connection to a source of suction pressure and connect all other selector valve boxes to a source of higher pressure.

6. An expression system for a reproducing piano having means to efi'ect the reproduction of expression indicated by the expression perforations in several different types of note sheets the expression perforations in which follow diflerentsystems for obtaining varieties of expression, said means including a tracker having a plurality of expression holes some of which are arranged to register with the expression perforations in each of several different types of note sheets, in combination with means'to select any one of several diiferent combinations of expression holes in said tracker corresponding with the expression perforations in the particular selected type of note sheet for the control of expression devices in the system appropriate to that note sheet.

7. An expression system for a reproducing piano including, in combination, a tracker having a plurality of expression holes, expression devices, and means operable to connect said expression devices selectively with any one of several predetermined combinations of expression holes.

8. An expression system for a reproducing piano including, in combination, a tracker having a plurality of expression holes, expression devices, and means operable to connect said expression devices selectively with predetermined combinations of expression holes thereby conditioning the system to produce substantially equivalent expression effects with several different types of note sheets.

9. An expression system for a reproducing piano including a tracker having, in combination, a plurality of expression holes, and means to select predetermined combinations of said expression holes corresponding with the expression perforations in several predetermined types of note sheets to control expression devices of the system in accordance with the system of expression perforations in said types of note sheets.

'10. An expression system for a reproducingpiano including a tracker having, in combination, a plurality of expression holes, expression devices, and manually-controlled means selectively to connect said expression devices operable with any one of several predetermined combinations of expression holes.

11. An expression system for a reproducing piano including, in combination, a tracker having a plurality of expression holes, a plurality of expression devices, and manually-controlled means to select a certain group of expression holes to render active' a certain portion onlyof the expression devices, and to select another group of expression holes to render active a different portion of the expression devices.

12. An expression system for a reproducing piano having means to efiect the reproduction of expression indicated by the expression control means of several different types of note sheets the expression control means of which follow different systems for obtaining varieties of expression, said means including, in combination, expression devices, controlling means for said expression devices governed by the expression control means of each of several different types of note sheets, and means to select any one of several combinations of controlling means corresponding with the expression controlling means of the selected type of note sheet for the proper control of said expression devices.

13. A reproducing piano having means to condition it to play several note sheets -havving different systems of expression perforations, said means including, in combination, an expression system having expression devices, a tracker having a plurality of expression holes adapted to be controlled by the expression perforations in the several note sheets, and means selectively to connect said expression devices operable with the expression holes corresponding to the expression perforations in a selected note sheet.

In testimony whereof, I have signed my name to this specification.

SAMUEL H. PERRON. 

